Satellites and Space Stations

Satellites and Space Stations

On clear nights you can watch satellites pass overhead. The biggest and brightest are visible even with the naked eye, but a good pair of binoculars will let you see even more satellites in the night sky. If you know where to look, you can track the passing of everything from commercial telecommunications satellites to the International Space Station (ISS).

Even with binoculars, some satellites appear simply as bright points of light moving quickly across the sky. The light that you see is sunlight reflecting off the satellite's surface. Because you need reflected sunlight to see a satellite, the best time to look for them is generally about an hour after sunset or an hour before sunrise. During the middle of the night, most satellites are fully in Earth's shadow.

To find out which satellites pass over your location and when to see them, visit heavens-above.com, select your location, and check predictions for several listed satellites. The table will tell you when the satellite will pass overhead and where in the sky to look.

The ISS is one of the easiest to spot. It is brighter than almost anything in the sky besides the moon, and it moves across the sky faster than most airplanes.

The Moon

The Moon

With the power of binoculars you should be able to spot details of the lunar surface such as the dark plains of cooled lava known as maria; the pale, crater-scarred lunar highlands; and many large craters. To find one of the largest and most impressive lunar craters, imagine the moon as a clock face and look at the 6 o'clock position, where you should see a large crater with white rays extending out from its edges. This crater is called Tycho, and the meteor that formed it slammed into the moon about 25 million years ago. The white rays are rock and dust thrown upward by the impact.

For the best view of lunar craters, look along the daylight side of the terminator—the line between the dark side of the moon and the sunlit side. Along this boundary, objects cast longer shadows, which makes the moon's topography stand out more clearly. Because the terminator moves across the lunar surface as the moon's phases shift, you should be able to see a different section of the every few nights.

During the waxing crescent phase, when the moon looks like just a crescent-shaped sliver in the western sky, your binoculars can reveal the rest of the lunar disc, faintly lit by sunlight reflected from Earth.